ctty-input.c

/* _hurd_ctty_input -- Do an input RPC and generate SIGTTIN if necessary. Copyright (C) 1995,97,99 Free Software Foundation, Inc. This file is part of the GNU C Library. The GNU C Library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. The GNU C Library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with the GNU C Library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. */#include <hurd.h>#include <hurd/signal.h>/* Call *RPC on PORT and/or CTTY. If a call on CTTY returns EBACKGROUND, generate SIGTTIN or EIO as appropriate. */
error_t
_hurd_ctty_input (io_t port, io_t ctty, error_t (*rpc) (io_t))
{
error_t err;
if (ctty == MACH_PORT_NULL)
return (*rpc) (port);
do
{
err = (*rpc) (ctty);
if (err == EBACKGROUND)
{
/* We are a background job and tried to read from the tty. We should probably get a SIGTTIN signal. */if (_hurd_orphaned)
/* Our process group is orphaned. Don't stop; just fail. */
err = EIO;
else
{
struct hurd_sigstate *ss = _hurd_self_sigstate ();
__spin_lock (&ss->lock);
if (__sigismember (&ss->blocked, SIGTTIN) ||
ss->actions[SIGTTIN].sa_handler == SIG_IGN)
/* We are blocking or ignoring SIGTTIN. Just fail. */
err = EIO;
__spin_unlock (&ss->lock);
if (err == EBACKGROUND)
{
/* Send a SIGTTIN signal to our process group. We must remember here not to clobber ERR, since the loop condition below uses it to recall that we should retry after a stop. */
__USEPORT (CTTYID, _hurd_sig_post (0, SIGTTIN, port));
/* XXX what to do if error here? *//* At this point we should have just run the handler for SIGTTIN or resumed after being stopped. Now this is still a "system call", so check to see if we should restart it. */
__spin_lock (&ss->lock);
if (!(ss->actions[SIGTTIN].sa_flags & SA_RESTART))
err = EINTR;
__spin_unlock (&ss->lock);
}
}
}
/* If the last RPC generated a SIGTTIN, loop to try it again. */
} while (err == EBACKGROUND);
return err;
}